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arXiv · 1306.1872

Applications of a nonlinear evolution equation I: the parton distributions in the proton

Xurong Chen·Jianhong Ruan·Rong Wang·Pengming Zhang·Wei Zhu
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Abstract

The parton distributions in the proton are evaluated dynamically using a nonlinear QCD evolution equation - the DGLAP equation with twist-4 (the GLR-MQ-ZSR) corrections - starting from a low scale $\mu^2$, where the nucleon consists of valence quarks. We find that the negative nonlinear corrections can improve the perturbative stability of the QCD evolution equation at low $Q^2$. Our resulting parton distributions of the proton with four free parameters are compatible with the existing databases. We show that the sea quark distributions exhibit a positive and flattish behavior at small $x$ and low $Q^2$. This approach provides a powerful tool to connect the quark models of the hadron and various non-perturbative effects on them at scale $\mu^2$ with the measured structure functions at high scale $Q^2>> \mu^2$.

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Xurong Chen, Jianhong Ruan, Rong Wang, Pengming Zhang, Wei Zhu. 2013-06-08. Applications of a nonlinear evolution equation I: the parton distributions in the proton. https://doi.org/10.1142/s0218301314500578

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